Ceiling fan system with brushless motor

ABSTRACT

A fan system includes a motor, a rotatable hub, and a plurality of fan blades. The motor is coupled with the hub by a hollow drive shaft, such that the drive system of the fan system is gearless. The motor is controlled by a PFC-based control module, which is in communication with sensors that are configured to sense parameters associated with operation of the fan system. The control module is configured to react in certain ways to certain conditions detected by the sensors, such that the fan system uses feedback-based control algorithms. A remote control panel is in communication with the control module. The remote control panel is operable to display fault conditions detected by the sensors. Blade retainers prevent fan blades from falling when a fan blade breaks free from the hub. Pins prevent the hub from falling when the hub breaks free from the rotor.

PRIORITY

This application claims priority from the disclosure of U.S. ProvisionalPatent Application Ser. No. 61/034,254, entitled “Ceiling Fan Systemwith Brushless Motor,” filed Mar. 6, 2008, the disclosure of which isincorporated by reference herein in its entirety. This application isalso a continuation-in-part of U.S. Non-Provisional patent applicationSer. No. 12/249,086, entitled “Ceiling Fan with Concentric StationaryTube and Power-Down Features,” filed Oct. 10, 2008, the disclosure ofwhich is incorporated by reference herein in its entirety, and whichclaims priority to U.S. Provisional Patent Application Ser. No.60/978,860, entitled “Ceiling Fan with Concentric Stationary Tube and/orSafety Features,” filed Oct. 10, 2007, the disclosure of which isincorporated by reference herein in its entirety.

BACKGROUND

A variety of fan systems have been made and used over the years in avariety of contexts. For instance, various ceiling fans are disclosed inU.S. Pat. No. 7,284,960, entitled “Fan Blades,” issued Oct. 23, 2007;U.S. Pat. No. 6,244,821, entitled “Low Speed Cooling Fan,” issued Jun.12, 2001; and U.S. Pat. No. 6,939,108, entitled “Cooling Fan withReinforced Blade,” issued Sep. 6, 2005. The disclosures of each of thoseU.S. patents are incorporated by reference herein. Another exemplary fanis disclosed in U.S. Pub. No. 2008/0008596, entitled “Fan Blades,”published Jan. 10, 2008, the disclosure of which is also incorporated byreference herein. Alternatively, any other suitable fans may be used inconjunction with embodiments described herein.

The outer tip of a fan blade or airfoil may be finished by the additionof an aerodynamic tip or winglet. Merely exemplary winglets aredescribed in U.S. Pat. No. 7,252,478, entitled “Fan BladeModifications,” issued Aug. 7, 2007, the disclosure of which isincorporated by reference herein. Additional winglets are described inU.S. Pub. No. 2008/0014090, entitled “Cuffed Fan Blade Modifications,”published Jan. 17, 2008, filed Sep. 25, 2007, the disclosure of which isincorporated by reference herein. Still other exemplary winglets aredescribed in U.S. Design Pat. No. D587,799, entitled “Winglet for a FanBlade,” issued Mar. 3, 2009, the disclosure of which is incorporated byreference herein. In other variations, an angled extension may be addedto a fan blade or airfoil, such as the angled airfoil extensionsdescribed in U.S. Pub. No. 2008/0213097, entitled “Angled AirfoilExtension for Fan Blade,” published Sep. 4, 2008, the disclosure ofwhich is incorporated by reference herein. Other suitable structuresthat may be associated with an outer tip of an airfoil or fan blade willbe apparent to those of ordinary skill in the art. Alternatively, theouter tip of an airfoil or fan blade may be simply closed, or may lackany similar structure at all.

The interface of a fan blade and a fan hub may also be provided in avariety of ways. For instance, an interface component is described inU.S. Non-Provisional patent application Ser. No. 12/233,783, entitled“Aerodynamic Interface Component for Fan Blade,” filed Sep. 19, 2008,the disclosure of which is incorporated by reference herein.Alternatively, the interface of a fan blade and a fan hub may includeany other component or components, or may lack any similar structure atall.

Fans may also include a variety of mounting structures. For instance, afan mounting structure is disclosed in U.S. Non-Provisional patentapplication Ser. No. 12/203,960, entitled “Ceiling Fan with AngledMounting,” filed Sep. 4, 2008, the disclosure of which is incorporatedherein. In addition, a fan may include sensors or other features thatare used to control, at least in part, operation of a fan system. Forinstance, such fan systems are disclosed in U.S. Non-Provisional patentapplication Ser. No. 12/249,086, entitled “Ceiling Fan with ConcentricStationary Tube and Power-Down Features,” filed Oct. 10, 2008, thedisclosure of which is incorporated by reference herein; PCT PatentApplication Serial No. PCT/US09/32935, entitled “Automatic ControlSystem for ceiling fan Based on Temperature Differentials,” filed Feb.3, 2009, the disclosure of which is incorporated by reference herein;and U.S. Non-Provisional patent application Ser. No. 12/336,090,entitled “Automatic Control System to Minimize Oscillation in CeilingFans,” filed Dec. 16, 2008, the disclosure of which is incorporated byreference herein. Alternatively, any other suitable mounting structuresand/or fan systems may be used in conjunction with embodiments describedherein.

While a variety of fans and fan systems have been made and used, it isbelieved that no one prior to the inventors has made or used a fansystem as described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims which particularly pointout and distinctly claim the invention, it is believed the presentinvention will be better understood from the following description ofcertain examples taken in conjunction with the accompanying drawings, inwhich like reference numerals identify the same elements and in which:

FIG. 1 depicts a bottom view of an exemplary fan system;

FIG. 2 depicts a perspective view of the fan system of FIG. 1;

FIG. 3 depicts a side view of a hub assembly of the fan system of FIG.1, with the fan blades removed;

FIG. 4 depicts a perspective view of the hub assembly of FIG. 3;

FIG. 5 depicts a top view of the hub assembly of FIG. 3;

FIG. 6 depicts a bottom view of the hub assembly of FIG. 3, withlighting components removed;

FIG. 7 depicts a cross-sectional view of the hub assembly of FIG. 3;

FIG. 8 depicts a perspective view of a motor heat sink of the fan systemof FIG. 1;

FIG. 9 depicts a bottom view of a hub of the fan system of FIG. 1;

FIG. 10 depicts motor controls of the fan system of FIG. 1;

FIG. 11 depicts an exemplary control panel on a remote control devicefor the fan system of FIG. 1;

FIG. 12 depicts a plan view of a safety cable securing a portion of thefan system of FIG. 1 to a building roof structure;

FIG. 13 depicts a partial cross-sectional view of the fan system of FIG.1, showing a safety cable securing a portion of the fan to a hangingfixture;

FIG. 14 depicts a partial top perspective view of the fan system of FIG.1, showing fan blade retention features;

FIG. 15A depicts a partial bottom perspective view of the fan system ofFIG. 1, showing fan blade retention features;

FIG. 15B depicts a partial bottom perspective view of the fan system ofFIG. 1, showing fan blade retention features, and with a light coverremoved;

FIG. 16 depicts an exploded view showing the fan blade retentionfeatures of FIGS. 14-15; and

FIG. 17 depicts a perspective view of the blade retention member ofFIGS. 14-16.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the invention may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presentinvention, and together with the description serve to explain theprinciples of the invention; it being understood, however, that thisinvention is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the invention shouldnot be used to limit the scope of the present invention. Other examples,features, aspects, embodiments, and advantages of the invention willbecome apparent to those skilled in the art from the followingdescription, which is by way of illustration, one of the best modescontemplated for carrying out the invention. As will be realized, theinvention is capable of other different and obvious aspects, all withoutdeparting from the invention. Accordingly, the drawings and descriptionsshould be regarded as illustrative in nature and not restrictive.

Fan System Overview

As shown in FIGS. 1-2 and 11, the fan system (10) of the present exampleincludes a fan that comprises a motor (20), a hub (40), and blades (50);and a remote control (500). In the present example, fan (10) (i.e., withblades (50)) has a diameter of approximately 12 feet. In othervariations, fan (10) has a diameter between approximately 6 feet,inclusive, and approximately 24 feet, inclusive. Alternatively, the fanmay have any other suitable dimensions. Each of the foregoingcomponents, among others, will be described in greater detail below, aswell as various ways in which fan (10) may be operated. It should beunderstood, however, that the components described below are mereexamples. Such components may be varied, modified, substituted,supplemented, or omitted as desired. Various ways in which componentsdescribed below may be varied, modified, substituted, supplemented, oromitted, as well as ways in which operation of fan (10) may be varied,modified, or supplemented, will be apparent to those of ordinary skillin the art in view of the teachings herein.

Fan Blades

A variety of types of fan blades (50) may be used with fan system (10)of the present example. For instance, fan blades (50) have an airfoilshape in the present example, and may be configured in accordance withthe teachings of U.S. Pat. No. 7,284,960, entitled “Fan Blades,” issuedOct. 23, 2007; U.S. Pat. No. 6,244,821, entitled “Low Speed CoolingFan,” issued Jun. 12, 2001; and/or U.S. Pat. No. 6,939,108, entitled“Cooling Fan with Reinforced Blade,” issued Sep. 6, 2005. Thedisclosures of each of those U.S. patents are incorporated by referenceherein. As another merely illustrative example, fan blades (50) may beconfigured in accordance with the teachings of U.S. Pub. No.2008/0008596, entitled “Fan Blades,” published Jan. 10, 2008, thedisclosure of which is also incorporated by reference herein. As yetanother merely illustrative example, fan blades (50) may be configuredin accordance with the teachings of U.S. Provisional Application No.61,109,220, entitled “Multi-Part Modular Airfoil Section and Method ofAttachment Between Parts,” filed Oct. 29, 2008, the disclosure of whichis incorporated by reference herein. Alternatively, any other suitableconfigurations for fan blades (50) may be used in conjunction withembodiments described herein.

In the present example, fan blades (50) are formed of aluminum throughan extrusion process, and have a substantially uniform cross-sectionalong their length. However, it should be understood that fan blades(50) may be made of any other suitable material or materials, includingcombinations thereof. By way of example only, fan blades may be formedof a combination of a metal and a plastic, a foam core with a durableouter skin, or any other suitable material or combination of materials.Similarly, any suitable method of forming fan blades (50) may be used,including but not limited to roll forming, molding, stamping andbending, etc. Fan blades (50) may even be twisted, if desired, and mayhave a non-uniform cross section if desired.

In addition, fan blades (50) that are used with fan system (10) of thepresent example may include a variety of modifications. For instance,the outer tip of each fan blade (50) may be finished by the addition ofan aerodynamic tip or winglet (52). By way of example only, winglets(52) may be configured in accordance with the teachings of U.S. Pat. No.7,252,478, entitled “Fan Blade Modifications,” issued Aug. 7, 2007, thedisclosure of which is incorporated by reference herein. As anothermerely illustrative example, winglets (52) may be configured inaccordance with the teachings of U.S. Pub. No. 2008/0014090, entitled“Cuffed Fan Blade Modifications,” published Jan. 17, 2008, filed Sep.25, 2007, the disclosure of which is incorporated by reference herein.As yet another merely illustrative example, winglets (52) may beconfigured in accordance with the teachings of U.S. Design Pat. No.D587,799, entitled “Winglet for a Fan Blade,” issued Mar. 3, 2009, thedisclosure of which is incorporated by reference herein.

In still other variations, an angled extension may be added to the freeend of each fan blade (50), such as the angled airfoil extensionsdescribed in U.S. Pub. No. 2008/0213097, entitled “Angled AirfoilExtension for Fan Blade,” published Sep. 4, 2008, the disclosure ofwhich is incorporated by reference herein. Other suitable structuresthat may be associated with an outer tip of each fan blade (52) will beapparent to those of ordinary skill in the art in view of the teachingsherein. Alternatively, the outer tip of each fan blade (50) may besimply closed or capped, or may lack any similar structure at all.

Fan Hub

As shown in FIGS. 3-7 and 9, the fan hub (40) of the present exampleincludes a plurality of tab-like mounting members (42). Each mountingmember (42) is configured to receive a respective fan blade (50). Fanblades (50) may be secured to mounting members (42) using any suitablestructures or techniques, including but not limited to one or more bolts(304) or other fasteners. For instance, as shown in FIGS. 14-17, fansystem (10) may include blade retention components that are configuredto retain blades (50). In particular, several retainer members (300) maybe joined relative to each blade (50) using bolts (304) or any othersuitable fasteners. Retainer members (300) are configured to provide asafety feature for fan system (10). In particular, each retainer member(300) is joined to two adjacent mounting members (42) and two adjacentfan blades (50), as will be described in greater detail below. In theevent that a fan blade (50) breaks free of its mounting member (42), theretainer members (300) that are secured to that fan blade (50) mayprevent the fan blade (50) from falling to the ground or otherwiseflying free of fan system (10). Similarly, in the event that a mountingmember (42) breaks free from hub (40), the retainer members (300) thatare secured to that mounting member (42) will prevent the mountingmember (42) (and the fan blade (50) that is coupled with that mountingmember (42)) from falling to the ground or otherwise flying free of fansystem (10).

As shown in FIG. 17, retainer members (300) may be formed of metal thatis stamped into an “L” shape, then bent to facilitate overlapping ofadjacent retainer members (300). Of course, any other suitablematerial(s) and/or method(s) of manufacture may be used. The “L” shapeof retainer members (300) in the present example provides a radialportion (320) and a circumferential portion (322). In particular, whenretainer members (300) are incorporated into fan system (10) as shown inFIG. 14, radial portions (320) extend radially outward relative to theaxis about which fan blades (50) are rotated; while circumferentialportions (322) extend circumferentially about that axis. Circumferentialportions (322) may be arcuate, such that circumferential portion (322)is not necessarily a straight edge defining a perfectly right angle withradial portion (320). An opening (324) is formed at the corner definedby radial and circumferential portions (320, 322) in this example.Similarly, an opening (326) is formed at the free end of radial portion(320); while another opening (328) is formed at the free end ofcircumferential portion (322). It should be understood, however, thatretainer members (300) may have any other suitable configuration.Alternatively, retainer members (300) may be supplemented or evenomitted altogether, if desired.

As shown in FIG. 16, when mounting a blade (50) to hub (40), the blade(50) may be slid onto a mounting member (42), such that openings (314)in the blade (50) line up with openings (310) in the mounting member(42). Two upper retainer members (300) may be positioned above the blade(50). In particular, the end of the circumferential portion (322) of afirst retainer member (300) may be positioned over the blade (50); whilethe radial portion (320) of a second retainer member (300) may bepositioned above that part of the circumferential portion (322) of thefirst retainer member (300). In this example, the opening (328) of thefirst retainer member (300) aligns with complementary openings (310,314) of mounting member (42) and fan blade (50). The opening (324) ofthe second retainer member (300) aligns with those same openings (310,314, 328); while the opening (326) of the second retainer member (300)aligns with the other complementary openings (310, 314) of mountingmember (42) and fan blade (50). The end of the circumferential portion(322) of the first retainer member (300) is “sandwiched” between theradial portion (320) of the second retainer member (300) and the fanblade (50), such that the radial portion (320) of the second retainermember (300) overlaps the end of the circumferential portion (322) ofthe first retainer member (300). A first bolt (304) is then insertedthrough aligned openings (310, 314, 326); and a second bolt (304) isinserted through aligned openings (310, 314, 324, 328). This process maybe repeated until all blades (50) are secured to the hub (40).

As another merely illustrative example, one or more wires, cables, orother components may be fed through the interior of each fan blade (50).Using an example with a wire, one end of the wire may be secured to hub(40) while the other end of the wire may be secured to the free end offan blade (50). Such a wire, cable, or other component(s) may thusprovide additional safety retention, such as when a mounting member (42)breaks free from hub (40), etc. Like retainer members (300), such awire, cable, or other component(s) may have sufficient strength to bearthe weight of at least one fan blade (50), and sufficient strength towithstand snapping and/or binding action that may occur when a blade(50) breaks free from hub (40), when a mounting member (42) breaks freefrom hub (40), etc. Furthermore, such a wire, cable, or othercomponent(s) may be used in addition to or in lieu of retainer members(300).

Of course, a variety of other structures and techniques may be used tosecure fan blades (50) to hub (40). By way of example only, any suitabletype of fastener other than bolts (304) may be used, including but notlimited to rivets, screws, welding, adhesives, epoxies, snap fittings,interference fittings, etc., including combinations thereof.Furthermore, retainer members (300) may be modified, substituted, orsupplemented in any suitable fashion, if not omitted altogether.

As shown in FIG. 9, hub (40) of the present example also includesseveral openings (46) formed therethrough. While openings (46) of thisexample have a substantially elliptical shape, it will be appreciatedthat other shapes may be used (e.g., trapezoidal, circular, elongateslits or slots, triangular, square, etc.). Openings (46) are configuredto permit airflow through hub (40). In particular, openings (46) providea path for heat to escape from motor (20) (above hub) and/or heat toescape from control electronics (below hub), which will be described ingreater detail below. While openings (46) are shown as extendinggenerally radially outwardly relative to the center of hub (40), itshould be understood that openings (46) may have any other suitableorientation (e.g., circumferential), to the extent that openings (46)have any perceivable orientation at all. A plurality of ribs (48) extendradially from the center opening of hub (40), between adjacent openings(46), providing additional rigidity for hub (40). Of course, likeopenings (46), ribs (48) are merely optional.

In addition or as an alternative to openings (46) in hub (40), one ormore openings may also be provided through bell (26) of motor (20)and/or through any other component of motor (20). By way of exampleonly, an opening formed through bell (26) may generate a funnelingeffect through one or more openings formed in rotor (22) and/or throughopenings (46) in hub (40). As another merely illustrative example,openings (46) in hub (40) may port air through the internal windings ofmotor (20) (e.g., where a motor (20) having an open frame is used). Itwill be appreciated that, in some instances, sufficient ventilation ofmotor (20) may enable motor (20) to operate at a cooler temperature(e.g., providing longer motor (20) life, etc.) and/or to operate at ahigher torque level on a continuous basis. As yet another merelyexemplary modification, the windings of stator (24) of motor (20) may beprovided with an overmold to improve thermal dissipation capabilities.Such an overmold material may improve thermal conductivity between wiresof the windings and the housing of stator (24), which may in turnimprove thermal conduction to the outside housing. Other suitablestructures, modifications, and techniques for providing desired thermalperformance will be apparent to those of ordinary skill in the art inview of the teachings herein.

As is also shown, mounting members (42) are oriented at an angle ofattack. By way of example only, such an angle of attack may beapproximately 8 degrees. Alternatively, an angle of attack for mountingmembers (42) may be between approximately 6 degrees, inclusive, andapproximately 10 degrees, inclusive. Alternatively, an angle of attackfor mounting members (42) may be between approximately 2 degrees,inclusive, and approximately 14 degrees, inclusive. The angle of attackfor mounting members (42) may alternatively be approximately zero, maybe less than zero (e.g., applying a negative sign before any of theabove-noted values or ranges), or may have any other suitable value orfall within any other suitable range. It should be understood, however,that fan blades (50) that are mounted to mounting members (42) need notnecessarily have the same angle of attack as mounting members (42).

Furthermore, there are a number of ways in which an “angle of attack”for a fan blade (50) may be defined. For instance, under one definition,such as where a fan blade (50) has a concave lower surface, an angle ofattack may be measured based on a plane extending from the lowermostpoint near the leading edge of the fan blade (50) and the lowermostpoint of the trailing edge of the fan blade (50) (e.g., as if a flatplate were placed across the bottom of the fan blade (50)). An angle ofattack for the fan blade (50) may be viewed as the angle of such a planerelative to a horizontal axis. Under such a definition, in some versionsof the fan system (10), the angle of attack may be approximately 6.54degrees or approximately 6.5 degrees. Alternatively, this angle ofattack may be between approximately 4.5 degrees, inclusive, andapproximately 8.5 degrees, inclusive. Alternatively, this angle ofattack may be between approximately 2 degrees, inclusive, andapproximately 8 degrees, inclusive. Alternatively, this angle of attackmay be between approximately zero degrees, inclusive, and approximately10 degrees, inclusive; or between approximately −1.7 degrees, inclusive,and approximately 10.3 degrees, inclusive. This angle of attack mayalternatively be approximately zero, may be less than zero (e.g.,applying a negative sign before any of the above-noted positive valuesor ranges; indicating that the leading edge is vertically positionedlower than the trailing edge of fan blade (50)), or may have any othersuitable value or fall within any other suitable range.

Yet another way in which angle of attack for fan blades (50) may bedefined includes the angle defined between the chord of a fan blade (50)and a horizontal axis. Under this definition, in some versions of fansystem (10), the angle of attack may be approximately 7.16 degrees orapproximately 7.2 degrees. Alternatively, this angle of attack may bebetween approximately 5 degrees, inclusive, and approximately 9 degrees,inclusive; or between approximately 5.2 degrees, inclusive, andapproximately 9.2 degrees, inclusive. Alternatively, this angle ofattack may be between approximately 3 degrees, inclusive, andapproximately 11 degrees, inclusive. Alternatively, this angle of attackmay be between approximately −1.0 degrees, inclusive, and approximately11.0 degrees, inclusive; or between approximately −1 degrees, inclusive,and approximately 12 degrees, inclusive. This angle of attack mayalternatively be approximately zero, may be less than zero (e.g.,applying a negative sign before any of the above-noted positive valuesor ranges; indicating that the leading edge is vertically positionedlower than the trailing edge of fan blade (50)), or may have any othersuitable value or fall within any other suitable range.

Suitable configurations for mounting members (42) and fan blades (50)for providing any of the above described angles of attack (under anydefinition) will be apparent to those of ordinary skill in the art inview of the teachings herein. For instance, to the extent that fanblades (50) are hollow, and mounting members (42) are inserted into theinterior of fan blades (50), a variety of structures within fan blades(50) may yield a variety of relationships between the angle of attack ofa mounting member (42) and the angle of attack of a fan blade (50). Inother words, these angles of attack do not need to be identical, thoughthey may be if desired.

The interface of each fan blade (50) and fan hub (40) of the presentexample may also be provided in a variety of ways. For instance, and asshown in FIGS. 14-16, an interface component (54) is provided at theinterface of each fan blade (50) and fan hub (40) in the presentexample. By way of example only, interface component (54) may beconfigured in accordance with the teachings in U.S. Non-Provisionalpatent application Ser. No. 12/233,783, entitled “Aerodynamic InterfaceComponent for Fan Blade,” filed Sep. 19, 2008, the disclosure of whichis incorporated by reference herein. Of course, interface component (54)may have any other suitable configuration. Alternatively, the interfaceof a fan blade (50) and a fan hub (40) may include any other componentor components, or may lack any similar structure at all.

Motor

In the present example, motor (20) is a permanent magnet brushless DCmotor. In particular, and as shown in FIG. 7, motor (20) has an inner,permanent magnet rotor (22) and an external stator (24) that includesselectively commutated windings. Of course, any other suitable motorconstruction, brushed, brushless or otherwise, including but not limitedto a brushless motor (20) with an external rotor (22) rotating about aninternal stator (24), may be used. In some versions, motor (20) has aback EMF constant that is equal to or greater than approximately 0.55VRMS/KPRM per every 1 VDC applied bus voltage to the windings of stator(24). For instance, back EMF may refer to back electromotive force;while VRMS may refer to volts root mean square; while KRPM may refer tothousand revolutions per minute; while VDC may refer to volts of directcurrent. Alternatively, motor (20) may have any other suitableperformance characteristics.

Motor (20) in the present example is provided within a housing. Thehousing of this example substantially and sealingly encloses rotor (22)and stator (24), such that motor (20) is completely enclosed and notventilated. Of course, in other versions, motor (20) may be ventilated,and does not necessarily need to be sealed. The top portion of thehousing, provided as a bell (26), is mounted to a hanging fixture (28),which is in turn mounted to a ceiling (210) as will be described ingreater detail below. In some versions, hanging fixture (28) comprises ametal tube. Another merely exemplary hanging fixture (28) is disclosedin U.S. Pub. No. 2008/0213097, entitled “Angled Airfoil Extension forFan Blade,” published Sep. 4, 2008, the disclosure of which isincorporated by reference herein. Still other suitable hanging fixtures(28) and other structures/techniques for securing fan system (10) to aceiling (210) or elsewhere will be apparent to those of ordinary skillin the art in view of the teachings herein.

The housing for motor (20) may be further defined by a heat sink (30).As shown in FIG. 8, heat sink (30) of this example comprises a pluralityof cooling fins (32), which extend generally tangentially from theexterior of heat sink (30). In particular, fins (32) are oriented suchthat they extend counterclockwise (when viewing fan (10) from a floor,looking toward ceiling (210)). It should be understood that a tangentialconfiguration of cooling fins (32) may provide an increased surfacearea, which may directly relate to the thermal dissipation ability(e.g., measured in degrees Celsius per Watt) of heat sink (30), andwhich may thereby minimize the heat rise associated with motor (20).Alternatively, fins (32) may have any other suitable orientation orconfiguration. While motor (20) of the present example may generatesignificant heat, which might otherwise suggest against including ahousing that substantially encloses and seals the motor (20), thepresence of cooling fins (32) may provide sufficient heat dissipation topermit such a housing configuration. Of course, motor (20) may have anyother suitable housing, such that bell (26) and heat sink (30) may bemodified, substituted, or supplemented as desired.

Motor (20) of the present example uses ball bearings (not shown), thoughany other suitable bearings (e.g., tapered roller bearings) orsubstitutes thereof may be used. For instance, fan (10) may also includea plurality of ball and/or roller bearings elsewhere, such as betweenhollow drive shaft (60) (described below) and stationary sleeve (70)(also described below).

In the present example, the configuration of motor (20) and othercomponents permits fan (10) to be operated in accordance with theteachings herein without a gearbox being present. In other words, rotor(22) drives hub (40) directly via drive shaft (60) in this examples. Ofcourse, in other variations, a gearbox or any other components betweenrotor (22) and hub (40) may be used.

The configuration of motor (20) of the present example also provides adegree of modularity, such that two or more rotors (22) and stators (24)may be coaxially stacked along a common shaft. For instance, two or morerotors (22) and stators (24) may be stacked along a common shaft inresponse to torque demands or other considerations. Such stacking mayeliminate a need to otherwise include extra gears or other components.In addition, heat sink (30) is extruded in the present example. Thus,the same housing die may be used to produce various housings toaccommodate motors (20) that vary in length due to stacking of rotors(22) and stators (24).

Motor (20) of the present example may have any number of properties incommon with the motor described in U.S. Pat. No. 6,710,505, entitled“Direct Drive Inside-Out Brushless Roller Motor,” issued Mar. 23, 2004,the disclosure of which is incorporated by reference herein. Forinstance, motor (20) may develop a relatively high back EMF in such amanner as to provide a relatively high ratio of stator (24) voltage torotor (22) speed. For some versions of a motor (20), if the back EMF ofmotor (20) is decreased, the effective amount of torque per applied ampto motor (20) may decrease linearly. In the present example, the coilsof stator (24) may be formed of a number of turns and a gauge of wirethat is selected to produce a ratio of stator (24) voltage to rotor (22)speed of at least approximately 10 RMS volts per 1000 RPM for an appliedstator (24) voltage of 24 RMS volts per phase. Similarly, motor (20) mayproduce a stator (24) voltage to rotor (22) speed of at leastapproximately 20 RMS volts per 1000 RPM for an applied stator (24)voltage of approximately 48 RMS volts per phase. Thus, in some versions,a motor (20) in a fan (10) whose blades (50) provide a 12 foot diametermay have a BEMF that is around 1000 VRMS/KRPM. Furthermore, motor (20)may be constructed such that stator (24) coils are formed of a number ofturns and a wire AWG selected to produce a ratio of stator (24) voltageto rotor (22) speed of at least approximately 250 VRMS per 1000 RPM foran applied bus voltage of approximately 400 VDC. The minimum ratio ofstator (24) voltage to rotor (22) speed may be a direct ratio of appliedbus voltage (e.g., the ratio of stator (24) voltage to rotor (22) speedmay be at least approximately 50 VRMS for an applied bus voltage ofapproximately 160 VDC). Alternatively, motor (20) may yield any othersuitable ratio of stator (24) voltage to rotor (22) speed, or have anyother suitable properties.

In some versions (e.g., where fan (10) has blades (50) providing a 12foot diameter), motor (20) may have a motor constant of approximately700 oz.-in./√(watt). Alternatively, the motor constant may be anywherebetween approximately 650 oz.-in./√(watt), inclusive and approximately750 oz.-in./√(watt), inclusive; between approximately 600oz.-in./√(watt), inclusive and approximately 800 oz.-in./√(watt),inclusive; between approximately 550 oz.-in./√(watt), inclusive andapproximately 850 oz.-in./√(watt), inclusive; between approximately 500oz.-in./√(watt), inclusive and approximately 900 oz.-in./√(watt),inclusive; or within any other suitable range. To double the torqueoutput of motor (20) on a continuous basis, the motor constant may beincreased by approximately √(2)(1.414) or by any other suitable factor.Other suitable motor constants for a motor (20) will be apparent tothose of ordinary skill in the art in view of the teachings herein.

Hollow Drive Shaft and Stationary Sleeve

In the present example, and as shown in FIG. 7, motor (20) isoperatively engaged with hub (40) via a hollow shaft (60). Inparticular, hollow shaft (60) is fixedly coupled with inner rotor (22)and hub (40). Hollow shaft (60) has a through bore providing an innerdiameter of approximately 1.5 inches. In other variations, the diameterof the through bore is between approximately 2 inches, inclusive, andapproximately 2.5 inches, inclusive. Of course, hollow shaft (60) mayhave a through bore of any other suitable diameter.

By way of example only, a merely illustrative drive shaft (60)configuration that may be used with fan system (10) of the presentexample is disclosed in U.S. Non-Provisional patent application Ser. No.12/249,086, entitled “Ceiling Fan with Concentric Stationary Tube andPower-Down Features,” filed Oct. 10, 2008, the disclosure of which isincorporated by reference herein.

A stationary sleeve (70) is inserted through hollow drive shaft (60) inthe present example. In particular, the top end (72) of sleeve (70) issecured to bell (26), which is provided as the top of motor (20)housing; while the bottom end (74) of sleeve (70) is secured to platform(80), which is described in greater detail below. Therefore, sleeve (70)remains stationary while hollow drive shaft (60) rotates duringoperation of fan (10). Sleeve (70) in this example is hollow, permittingitems such as wires, fluid conduits (e.g., water pipes), etc., to bepassed therethrough. Sleeve (70) of the present example has a throughbore providing an inner diameter of approximately 1.5 inches, though anyother suitable inner diameter may be provided. In the present example,wires (not shown) are passed through inner sleeve (70). Such wires mayprovide power and/or communication of commands/data to/from motorcontrol module (90), which will be described in greater detail below.Such wires may also be coupled with lights (100), speakers, securitydevices, heat sensors (e.g., sensors configured to detect a rapid risein temperature, as described in U.S. Non-Provisional patent applicationSer. No. 12/249,086, entitled “Ceiling Fan with Concentric StationaryTube and Power-Down Features,” filed Oct. 10, 2008, the disclosure ofwhich is incorporated by reference herein; sensors configured to detecttemperature exceeding a certain threshold, etc.), flame detectors (e.g.,infrared and/or ultraviolet sensors, etc.), smoke detectors, or othercomponents that are secured to platform (80) at the bottom of fan (10),which will be described in greater detail below. Still other suitablecomponents that may be positioned within inner sleeve (70) will beapparent to those of ordinary skill in the art in view of the teachingsherein. Furthermore, it will be appreciated that some variations mayhave no stationary inner sleeve (70), nothing passed through a hollowshaft (60), or may have no hollow shaft (60) at all (e.g., a solid shaftor some other structure or configuration is used, etc.).

Motor Control Module

Motor (20) of the present example is operated through a control module(90), which is positioned on the bottom of fan (10) in the presentexample. Like motor (20) of the present example, motor control module(90) is enclosed. However, unlike motor (20) of the present example,motor control module (90) of the present example is ventilated. In somevariations, motor control module (90) is located on the bottom of motor(20). In other variations, motor control module (90) is located onplatform (80), which is described in greater detail below. For instance,motor control module (90) may be located on the top surface of platform(80) with one or more heat sinks (92) or other components also beingmounted to platform (80). Alternatively, as shown in FIG. 10, a separateplate (94) or other feature may be provided between motor control module(90) and platform (80) for mounting motor control module (90). It willbe appreciated that locating motor control module (90) the motor (20)and/or below other components may make it easier to service ormaintenance motor control module (90). Alternatively, motor controlmodule (90) may be located above motor (20) or elsewhere.

By way of example only, control module (90) may be operable to rotatemotor (20), and hence, fan blades (50), from between approximately 10RPM, inclusive (e.g., at a “low” speed setting), to approximately 82RPM, inclusive (e.g., at a “high” speed setting), in either rotationaldirection. Adjustability of the rotation speed may be provided in asubstantially continuous, non-incremental fashion; or in a stepped,incremental fashion. Of course, any other suitable speeds or ranges ofspeeds may be used. In still other variations, the speed of motor (20)is not adjustable. In the present example, when a user commands fan (10)to change its direction of rotation as it is rotating, motor controlmodule (90) is configured to remove power to motor (20), wait untilmotor (20) reaches approximately 0 RPM, then switch the rotationdirection. Alternatively, motor control module (90) may be configured tonot wait until motor (20) reaches approximately 0 RPM or may otherwisereverse the rotation of fan blades (50) in any other suitable fashion.In either case, one or more sensors may communicate with motor controlmodule (90) to indicate the rotation speed and/or rotation direction offan (10).

Motor control module (90) of the present example also includesintegrated power factor correction (PFC). Such PFC may be provided by anoff-the-shelf power correct integrated circuit or in any other suitablefashion. The power factor controller of the present example develops a400V DC bus to drive motor (20), though any other suitable PFC or othertype of controller may be used. The use of PFC may reduce the RF noisethat is generated by fan system (10), which may in turn reduceinterference with other systems (e.g., RFID systems, cash registers,etc.) that are in the same facility as fan system (10).

Motor controller (90) may also include an internal AC/DC converter powersupply that operates over a universal voltage input range ofapproximately 85 volts, inclusive, to approximately 277 volts,inclusive, though any other suitable range may be used. As anothermerely illustrative example, fan system (10) may operate over a voltageinput range of approximately 100 volts, inclusive, to approximately 240volts, inclusive. By way of example only, motor controller (90) mayprovide local control of motor (20) through analog 0-10 V or 4-20 mAcurrent loop interfaces. As described in greater detail below, motorcontroller (90) may be coupled with one or more remote controls (500),and may communicate with a remote control (500) wirelessly (e.g.,through wireless X-Bee serial communication, etc.) and/or through wiredserial RS-232C or RS-485 interfaces, selectable through driveparameters. Drive parameters and system information may be stored in anonboard non-volatile memory device or otherwise. In addition, one ormore hall effect sensors may be used to generate sinusoidal signals(e.g., without an encoder), which may in turn be used to commutatestator (24) windings. In other variations, sensors (hall or otherwise)are not used.

By way of example only, use of sine wave control of motor (20) mayminimize audible noise. For instance, torque spikes that may begenerated by motor (20) may be amplified by long blades (50). Sine wavecontrol may thus reduce the overall noise level of fan system (10). Afeedback system that may be used to enable generation of sine wavecommutation may include a continuous feedback signal (e.g., using aresolver, etc.), digital devices (e.g., an encoder and/or hall effectsensors), and/or using any other components or techniques (e.g.,sensorless commutation components and techniques, etc.), includingcombinations thereof. Alternatively, motor (20) may otherwiseincorporate the use of sine waves to commutate stator (24) windings, ormay use commutation techniques or technologies that do not include useof sine waves.

Motor control module (90) may be configured to have one or moreself-protection features. For instance, and as will be described ingreater detail below, control module (90) may be configured to shut downin response to or otherwise respond to any of the following: the currentpassing through control module (90) exceeding a threshold; line voltagefalling below a threshold; an invalid hall sensor state; the temperatureof control module (90) or motor (20) exceeding a threshold (e.g., sensedusing a thermistor or other component); a condition detected by one ormore sensors that are coupled with control module (90) (e.g., anaccelerometer or heat sensor, such as is described below, etc.); and/orunder other conditions. As another merely illustrative example, motorcontrol module (90) (or some other component of fan system (10)) mayprovide power surge protection, such as with an inline fuse and/or ametal oxide varistor (MOV). For instance, if a voltage surge occurs, afuse may open when an MOV shunts current in excess of the fuse rating.With respect to temperature sensing and processing, control module (90)may be in communication with various temperature sensors in variouslocations, such as temperature sensors that are configured to sense thetemperature of stator (24), heat sink (30), one or more bearings,ambient temperature at remote control (500), ambient temperatureelsewhere in the facility in which fan system (10) is located, and/orother locations.

Control module (90) may shut fan (10) down by cutting off power to motor(20) (e.g., allowing it to coast and slow to a halt by friction),actively decelerating motor (20) in a gradual fashion, abruptly stoppingmotor (20) via electromechanical means (e.g., brakes), utilizing dynamicbraking (e.g., shorting windings in motor (20)), or in any otherfashion. Furthermore, the way in which fan (10) is shut down (and/or theway in which fan (10) otherwise reacts) may vary based on the particularcondition(s) detected. Once fan (10) has been shut down in response toone or more detected conditions (e.g., some condition other than theuser simply activating the “off” button (510)), control module (90) mayrequire a user to activate a “reset button” or other feature in orderfor fan (10) to again be operable. In addition, motor control module(90) may provide an optically isolated user input/output, cycle-by-cyclecurrent limiting, or other features. In the event that any of the aboveconditions is detected, or other events are detected, motor controlmodule (90) may communicate the same to remote control (500) and/or aremote computer as described below, via wire or wirelessly. Furthermore,some such events may be communicated while others are not (e.g., someevents may be merely processed by motor control module (90) alone).

In some versions, one or more thermistors or other component(s) is/areused to detect the temperature of motor (20) as it is running. Suchthermistor(s) or other component(s) may be in communication with motorcontrol module (90). As noted above, motor control module (90) may shutfan (10) down when motor (20) temperature exceeds a certain threshold.In addition or in the alternative, motor control module (90) may simplyslow fan (10) down (e.g., by throttling back on motor (20) to operate ata reduced torque level) when motor (20) temperature exceeds a certainthreshold to prevent motor (20) from overheating, without necessarilystopping fan (10). For instance, a first threshold may be used formerely slowing fan (10); while a second threshold (e.g., higher than thefirst threshold) may be used for stopping fan (10). Permitting fan (10)to continue running may help reduce the ambient temperature external tothe fan, which may in turn help reduce internal temperatures in fan(10). The motor control module (90) may continue to monitor temperaturesthat are internal to and/or external to fan (10), and may command motor(20) increase the rotation speed of fan (10) to remain below atemperature threshold. Suitable temperature values and ranges for suchthresholds will be apparent to those of ordinary skill in the art inview of the teachings herein. Control module (90) may thus be used tocompare the temperature of motor (20), a commanded rotation speed, anactual rotation speed, thermal trends (internal and/or external to fan(10)), and/or other factors to determine whether motor (20) should beslowed down or sped back up.

In addition, control module (90) may include a learning mode algorithm.By way of example only, such a mode may upon initial use “learn” acorrelation between speed of motor (20) and a referenced thermal readingto enable motor (20) to adjust quickly to the optimum speed for aspecific installation once the initial learning process has beencompleted. Other ways in which a control module (90) may “learn” andreact accordingly will be apparent to those of ordinary skill in the artin view of the teachings herein.

Motor control module (90) may also be configured to store a variety ofdiagnostic information. For instance, motor control module (90) maystore fault conditions (e.g., over-temperature, over-current,over-voltage, under-voltage, etc.), elapsed run time of the system,operating speed, or other information. Such storage may be provided byvolatile memory, non-volatile memory, or otherwise. In addition, motorcontrol module (90) may be configured to permit such information to beaccessed or communicated to a remote location, such as to a remotecontrol (500) or remote computer as described below.

It will be appreciated that, in some situations, the configuration ofmotor (20) and control module (90) may permit fan (10) to produce lessnoise than other fans that are of a relatively large size. For instance,in the present example, the configuration of motor (20) and controlmodule (90) is such that audible noise produced by fan system (10)having blades (50) that provide a diameter between approximately 6 feet,inclusive, and approximately 24 feet, inclusive, and that rotate atapproximately 82 RPM, is less than approximately 68 db or less thanapproximately 45 db (C scale) when measured at a distance ofapproximately 1 meter directly below hub (40). Alternatively, fan system(10) may operate at any other audible noise level, including but notlimited to less than approximately 57 db under the same conditionslisted above.

It should also be understood that control module (90) may beprogrammable such that control module (90) may be programmed baseduniquely on a given customer's particular specifications and/or baseduniquely on the environment in which fan system (10) will be installed.Such programming may include modification of control algorithms,incorporating various types of different sensors, etc. Such programmingmay be performed by coupling a programming device directly to controlmodule (90) and/or by coupling a programming device to remote control(500). Programmability of control module (90) may be provided at leastin part by extra pins and/or ports that are not being used by othercomponents of fan system (10).

Various control algorithms that may be implemented through controlmodule (90) are described below under the heading “Control Algorithms,”while other control algorithms that may be implemented through controlmodule (90) will be apparent to those of ordinary skill in the art inview of the teachings herein.

Platform Below Hub

As noted above, a platform (80) is secured to the hollow innerstationary sleeve (70) in the present example. Platform (80) thereforeremains stationary during operation of fan (10). In some variations, oneor more lights (100) or lighting fixtures are secured to platform (80).By way of example only, such lights (100) may be communicatively coupledwith a motion sensor or other device, such as to turn off lights (100)when motion is not detected over a certain time period and/or to turn onlights (100) when motion is detected. Lights (100) may be located withina center casting at the bottom of fan (10) and/or elsewhere. Lights(100) of the present example comprise a plurality LED lights, though anyother suitable types of lights may be used, including but not limited toincandescent, halogen, fluorescent (annular, compact, etc.), HBLEDtypes, or other type of lights (100). A cover (106) is provided overlights (100) in this example. For instance, cover (106) may comprise alens or a non-lens cover, may be formed of glass or plastic, and may betranslucent or transparent. Alternatively, cover (106) may be formed ofany other suitable material(s), may have any other suitable properties,or may even be omitted altogether. Similarly, lights (100) may simply beomitted altogether. In addition or in the alternative, one or morestrobe lights or other lights may be included with a proximity sensor orother sensor, and may activate (e.g., along with a claxon or otheralarm), when a person gets too close to fan (10) while it is operating.

In other variations, one or more speakers (e.g., as part of an overheadannouncement or background music system in a store or other facility,etc.) are secured to platform (80). In still other variations, securitysystem components (e.g., one or more mirrors, cameras, motion detectors,etc.) are secured to platform (80). Such components may be secured toplatform (80) in addition to or in lieu of lights (100).

In other variations, one or more sensors are secured to platform (80).By way of example only, such sensors may include one or more heatsensors (e.g., sensors that are configured to detect a rapid rise inheat, such as those disclosed in U.S. Non-Provisional patent applicationSer. No. 12/249,086, entitled “Ceiling Fan with Concentric StationaryTube and Power-Down Features,” filed Oct. 10, 2008, the disclosure ofwhich is incorporated by reference herein), one or more flame detectors(e.g., infrared and/or ultraviolet sensor(s)), smoke detectors, or anyother sensors. One merely exemplary flame detector that may be used as asensor is a SHARPEYE UV/IR sensor by Spectrex, Inc. of Cedar Grove, N.J.A merely exemplary heat detector device may comprise a BK-5601P heatdetector device from System Sensor of St. Charles, Ill. A merelyexemplary smoke detector may comprise a VESDA aspirating smoke detectorwith a laser detection chamber, by Xtralis, Inc. of Norwell, Mass. Othersuitable fire, heat, or smoke detectors may include video and/or lasertypes. Of course, any other suitable sensors, for flame detection, rapidrise in heat detection, smoke detection, or otherwise, may be used. Suchsensors may be secured to platform (80) in addition to or in lieu oflights (100) or other components.

Still other variations may include one or more sprinklers secured toplatform (80). As noted above, one or more fluid conduits such as waterpipes may be fed through stationary sleeve (70) to reach sprinklerssecured to the platform (80). Such sprinklers may include conventionalsprinkler heads, and be configured to spray water upon detection offlames, a rapid rise in heat, smoke, or other indication of a fire bysensors that are also secured to platform (80) or that are otherwise incommunication with a component in common with the sprinklers. Inaddition or in the alternative, such sprinklers may be in communicationwith a preexisting fire detection system at the facility or location inwhich fan system (10) is installed. Alternatively, sprinklers may beincorporated with fan system (10) using any other suitable structures ortechniques. Such sprinklers may be secured to platform (80) in additionto or in lieu of lights (100) or other components.

Of course, the foregoing are mere examples of components that may besecured to platform (80). Other components that may be secured toplatform (80), including combinations of such components, will beapparent to those of ordinary skill in the art in view of the teachingsherein.

In the present example, a dome (110) is mounted to the bottom ofplatform (80). In the present example, dome (110) is formed of aluminum,though any other suitable material or combination of materials may beused, including but not limited to plastic, glass, and/or any othersuitable material(s). In some other versions, dome (110) issubstantially translucent, permitting light to pass therethrough.Alternatively, dome (110) may be transparent or have other properties.To the extent that dome (110) is translucent and/or transparent, dome(110) may also include a plurality of internal radial spines (112) tospread light from lights that are somewhere within dome (110). Dome(110) is secured relative to platform (80) by a retainer (114), thoughany other suitable structures or techniques may be used. A gap isprovided between the upper annular edge of dome (110) and hub (40). Airmay be communicated into and/or out of this gap, such as to provideventilation of control module (90) as described above. Such ventilationmay be further facilitated by openings (46) formed in hub (40) asdescribed above. Furthermore, the gap between dome (110) and hub (40)may be complemented by a gap between the housing of motor (20) and hub(40), such that air may communicate into and/or out of either gap orboth gaps to provide heat ventilation for control module (90) and motor(20), as facilitated by openings (46) formed in hub (40). Of course,dome (110) is merely exemplary, and any other suitable variationsthereof may be used; or dome (110) may be omitted altogether.

Safety Mechanisms

As shown in FIGS. 4 and 7, the bottom of motor (20) housing is definedby a base plate (34), which is secured to heat sink (30) and bell (26)via bolts (36). The outer perimeter of base plate (34) extends radiallyoutwardly beyond the outer perimeter of heat sink (30) in this example,providing a flange. Bearings (37) are provided between drive shaft (60)and bell (26), as well as between drive shaft (60) and base plate (34),to permit rotation of drive shaft (60) relative to bell (26), heat sink(30), and base plate (34). Bell (26), heat sink (30), and base plate(34) are all secured relative to sleeve (70) and mounting fixture (28),and thus remain stationary during operation of fan (10).

A plurality of pins (38) extend radially inwardly from the top of thehub (40), as shown in FIGS. 4 and 7, above the base plate (34). While agap is provided between the outer circumference of the base plate (34)and the interior of the top portion (vertical rim) of hub (40) to permitrotation of hub (40) relative to base plate (34), pins (38) have alength that exceeds this gap. In particular, pins (38) are configuredsuch that, in the event that hub (40) loses support at its interior anddrops relative to base plate (34), pins (38) will engage base plate (34)to prevent hub (40) from completely falling. Pins (38) of this examplethus have sufficient strength and rigidity to bear the weight of hub(40) and blades (50). In the present example, pins (38) are arrangedcircumferentially spaced about the perimeter of hub (40), angularlylocated between fan blade mounting members (42). It will be appreciated,however, that pins (38) may be arranged in any other suitable fashion.Furthermore, pins (38) may be modified, substituted, supplemented, oromitted as desired.

Another safety mechanism that may be included in fan system (10)comprises two cables (200, 202). In this example, and as shown in FIG.12, an upper cable (200) is secured to the ceiling (210) or some otherstructure associated with a roof. Hanging fixture (28) may have atransverse opening formed completely therethrough, such that cable (200)may be passed through this opening. Cable (200) may further be passedover a building roof structure (e.g., the structure that hanging fixture(28) is mounted to, such as a roof support at the ceiling (210)). Theends of cable (200) may be secured together using a fastener (204)(e.g., clevis, clamp, etc.) or using any other suitable device(s). Whilecable (200) does not provide any structural support to any component offan system (10) during normal operation of fan system (10), cable (200)may have sufficient strength such that, in the event that hangingfixture (28) breaks free from the roof structure, cable (200) willprevent fan system (10) from falling to the ground.

As shown in FIGS. 7 and 13, lower cable (202) may be secured relative tohanging fixture (28) and platform (80). In particular, an anchor (206)is secured within the interior of hanging fixture (28). The upper end oflower cable (202) is fixedly secured to anchor (206). The lower end oflower cable (202) is secured transversely to a bolt (104), which issecured to platform (80). In the present example, the length of bolt(104) and the dimensions of the other components of fan (10) areconfigured such that no components of fan (10) may pass downward beyondthe bolt (104). In other words, the length of bolt (104) is greater thanthe inner diameter of openings in components that are located above bolt(104). While the cable (202) and bolt (104) do not provide structuralsupport to any component of fan (10) during normal operation of fan(10), cable (202) and bolt (104) are configured to bear the weight ofthe entire fan (10) in the event that any component of fan (10) (e.g.,hub (40), motor (20), hanging fixture (28), etc.) becomes disengagedfrom the ceiling (210) or from any other component of fan (10). In otherwords, lower cable (202) may have sufficient strength such that, in theevent that a portion of fan system (10) breaks free from the hangingfixture (28), cable (202) will prevent fan system (10) from falling tothe ground.

While two safety cables (200, 202) are used in the present example, itshould be understood that only one safety cable may be used if desired.For instance, a single safety cable may be both secured to the roofstructure at the ceiling (210) and to bolt (104) at platform (80), suchthat the safety cable extends beyond the full length of hanging fixture(28). Alternatively, any other suitable configuration or arrangement ofone or more safety cables may be used. It should also be understood thatany suitable alternatives to cables (200, 202) may be used, includingbut not limited to rods, chains, etc. Furthermore, safety cables orsimilar components may be omitted altogether, if desired. Other suitablestructures and ways in which safety mechanisms may be provided will beapparent to those of ordinary skill in the art in view of the teachingsherein.

Torque Parameters

Motor (20) of the present example is operable to generate a broad rangeof torque and horsepower. By way of example only, motor (20) may providetorque selectively ranging from 0 to approximately 850 in-lbs.,inclusive. Motor (20) may also provide torque selectively ranging from 0to approximately 53 in-lbs., inclusive. Alternatively, motor (20) mayprovide torque among any of the following ranges, in which all of thefollowing values are merely approximate, all of the following upper andlower boundaries are inclusive within the stated ranges, and all of thefollowing values are in units of in-lbs.: 0 to 50; 0 to 308; 0 to 567; 0to 825; 0 to 1,083; 0 to 1,342; 0 to 1,600; 0 to 1,859; 0 to 2,376;among other possible ranges. None of those ranges should be viewed asexcluding upper limits or lower limits that are explicitly set forth.Furthermore, none of those ranges should be viewed as providing exactnumbers for the upper limit and lower limit—those limits are mereapproximations.

Motor (20) may drive the drive shaft (60) with a horsepower ranging from0 to approximately 0.7328 HP, inclusive. Motor (20) may also drive thedrive shaft (60) with a horsepower ranging from 0 to approximately 0.097HP, inclusive. Alternatively, motor (20) may provide horsepower amongany of the following ranges, in which all of the following values aremerely approximate, all of the following upper and lower boundaries areinclusive within the stated ranges, and all of the following values arein units of HP: 0 to 0.13; 0 to 0.55; 0 to 0.93; 0 to 1.06; 0 to 1.22; 0to 1.34; 0 to 1.40; 0 to 1.42; or 0 to 1.58; among other possibleranges. None of those ranges should be viewed as excluding upper limitsor lower limits that are explicitly set forth. Furthermore, none ofthose ranges should be viewed as providing exact numbers for the upperlimit and lower limit—those limits are mere approximations.

These above-noted ranges may be achieved with motor (20) of the presentexample even without a gearbox or similar device being used. However, inother embodiments, a gearbox or other device may be used. It will beappreciated that the torque values and ranges, horsepower values andranges, and other parameters described herein and shown in the attachedtable are merely exemplary, and that a motor (20) may be configured toprovide any other suitable values and ranges of torque and horsepower,and may operate under any other suitable parameters.

Control Algorithms

Fan system (10) of the present example may include control algorithmsthat are a function of certain conditions within the room or facility inwhich fan (10) is located. Such control algorithms may be implementedthrough control module (90), based at least in part on feedback obtainedthrough various types of sensors that may be in communication withcontrol module (90). For instance, in some variations, a firsttemperature sensor is provided near the ceiling of the room in which thefan is located (e.g., on platform (80) described above, on the ceiling(210) itself, etc.); while a second temperature sensor is provided nearthe floor of the room. Such a pair of temperature sensors may be used todetermine the difference between the temperatures at or near the ceiling(210) and floor, and such a difference in temperature may be indicativeof a stratification condition or undesirable temperature distribution.The temperature difference may be used to control fan (10) in responseto the temperature difference. For instance, if the temperaturedisparity between the floor and the ceiling (210) passes a threshold,the speed of fan (10) may be automatically increased. When thetemperature disparity falls back below the threshold (e.g., such thatthe temperature near the ceiling (210) is approximately equal to thetemperature near the floor, etc.), fan (10) speed may be decreased backto its prior level, or fan (10) may be stopped. Once the temperaturedisparity rises again past a certain threshold, fan (10) may again beactivated and controlled as described above. Various ways in which sucha destratification control system may be provided (e.g., within fansystem (10) of the present example) are described in PCT PatentApplication Serial No. PCT/US09/32935, entitled “Automatic ControlSystem for ceiling fan Based on Temperature Differentials,” filed Feb.3, 2009, the disclosure of which is incorporated by reference herein.Other ways in which a fan (10) may be automatically controlled based ontemperature differences within a room or facility will be apparent tothose of ordinary skill in the art in view of the teachings herein.

Fan system (10) of the present example may also include controlalgorithms that are provided as safety features. For instance, fansystem (10) may include one or more accelerometers, heat sensors, smokedetectors, anemometers, and/or other components that are configured tosense a mechanical obstruction to the rotating blades (50), an imbalancecondition (e.g., fan (10) is wobbling), a fire (e.g., as a rapid rise intemperature and/or smoke), high winds (e.g., when fan (10) is locatedoutdoors), and/or other conditions. Such components may includeoff-the-shelf components and/or may have adjustable sensitivity. Forinstance, in some versions, an off-the-shelf heat sensor is mounted toplatform (80) to detect a rapid rise in temperature. Alternatively, anoff-the-shelf smoke detector may be coupled with platform (80). Anexemplary use of such a heat sensors and smoke detectors is disclosed inU.S. Non-Provisional patent application Ser. No. 12/249,086, entitled“Ceiling Fan with Concentric Stationary Tube and Power-Down Features,”filed Oct. 10, 2008, the disclosure of which is incorporated byreference herein. Additional sensors whose feedback may be factored intoa control algorithm may include one or more flame detectors (e.g.,infrared and/or ultraviolet sensor(s)), smoke detectors, or any othersensors. One merely exemplary flame detector that may be used as asensor is a SHARPEYE UV/IR sensor by Spectrex, Inc. of Cedar Grove, N.J.A merely exemplary heat detector device may comprise a BK-5601P heatdetector device from System Sensor of St. Charles, Ill. A merelyexemplary smoke detector may comprise a VESDA aspirating smoke detectorwith a laser detection chamber, by Xtralis, Inc. of Norwell, Mass. Ofcourse, any other suitable sensors, for flame detection, rapid rise inheat detection, smoke detection, or other type(s) of detection, may beused.

Such components may be in communication with control module (90), whichmay be configured to bring fan (10) to a controlled safety stop (orprovide some other type of reaction) in response to a signal from one ormore accelerometers and/or other components that indicates a safetycondition such as a mechanical obstruction. For instance, control module(90) may bring fan (10) to a stop in response to detection of conditionsindicative of a fire in the facility in which fan (10) is installed,conditions indicative of blades (50) impacting an object, conditionsindicative of an imbalance in fan (10), etc. As noted above, the safetystop may be gradual or abrupt, which may vary based on the sensedcondition or may be the same for all safety condition. Various ways inwhich a fan (e.g., within fan system (10) of the present example) may becontrolled in response to a rapid rise in heat, the presence of smoke, afan blade (50) striking an obstruction, or in response to otherconditions are described in U.S. Non-Provisional patent application Ser.No. 12/249,086, entitled “Ceiling Fan with Concentric Stationary Tubeand Power-Down Features,” filed Oct. 10, 2008, the disclosure of whichis incorporated by reference herein. By way of example only, controlmodule (90) may react to such conditions by reducing the rotation speedof motor (20) to a reduced non-zero level, allow motor (20) to “coast”to a stop, cause active braking of motor (20) or hub (40), etc. Asanother merely illustrative example, a software-based (orotherwise-based) “notch filter” may be implemented to prevent fan (10)from operating at a speed that creates undesirable audible effects dueto certain dynamics associated with the installation. Other ways inwhich a fan (10) may be automatically controlled based on a variety ofconditions (e.g., blade obstruction, rapid heat rise, smoke, etc.) willbe apparent to those of ordinary skill in the art in view of theteachings herein.

Similarly, fan system (10) of the present example may be controlled toprevent undesirable oscillation or wobbling of fan (10). For instance,various ways in which a fan (e.g., within fan system (10) of the presentexample) may be controlled to prevent oscillation or wobbling aredisclosed in U.S. Non-Provisional patent application Ser. No.12/336,090, entitled “Automatic Control System to Minimize Oscillationin Ceiling Fans,” filed Dec. 16, 2008, the disclosure of which isincorporated by reference herein. Other ways in which a fan (10) may beautomatically controlled to prevent a variety of conditions (e.g.,undesirable oscillation or wobbling, etc.) will be apparent to those ofordinary skill in the art in view of the teachings herein.

It will also be appreciated that the same sensors may be used to detectdifferent conditions. For instance, an accelerometer may be used todetect both a mechanical obstruction or impact by a fan blade (50) andan imbalance of fan (10). By way of example only, thresholds and/ortimers may be used to distinguish between an impact and an imbalance.Similarly, the same temperature sensor that is used to detect heat nearthe ceiling for destratification purposes may also be used to detect afire for purposes of shutting fan (10) down. Other ways in which sensorsor other components may be used to serve multiple purposes will beapparent to those of ordinary skill in the art in view of the teachingsherein.

In some contexts, fan system (10) may be positioned near one or moresprinkler heads mounted to the ceiling of a building, such as may befound in some ESFR (Early Suppression, Fast Response) systems. In somesuch instances, blades (50) of fan (10) may have sufficient length suchthat they may pass under such sprinkler heads, such that one or moreblades (50) may present an obstacle to water being sprayed from asprinkler head. It may (or may not) be desirable in some instances toprevent fan (10) from stopping in such a way that a blade (50) ispositioned directly under a sprinkler head or sufficiently under asprinkler head to adversely affect the flow of water from the sprinklerhead. For instance, this may (or may not) be of particular concern wherefan (10) is brought to an “emergency stop” upon detection of a rapidrise in heat, detection of a flame, detection of smoke, or detection ofany other indication of a fire. Of course, it may also be of concernwhen fan (10) is stopped in the absence of an emergency. Alternatively,stopping a fan (10) such that one or more blades (50) are located atleast partially under a sprinkler head may pose no issues or problemswhatsoever. In other words, the location of a fan (10) and its blades(50) may have no adverse effects whatsoever on operation of an ESFRsystem, even if one or more of the blades (50) is within the path ofwater being sprayed by an overhead sprinkler.

There are a variety of ways in which a fan (10) may be brought to a stopin a manner such that a blade (50) is not undesirably positioned atleast partially under a sprinkler head. For instance, an encoder wheeland sensor or other device(s) may be used to sense the rotationalposition of rotor (22), which may be indicative of the rotationalposition of blades (50). A controller that is in communication with sucha position sensor may also be configured to receive instructionsindicating one or more rotational positions at which fan (10) shouldstop and/or one or more rotational positions at which fan (10) shouldnot stop. Such instructions may be programmed into the controller uponinstallation of fan (10) or at any other suitable time. For instance,upon installation of fan (10), an installer may manually rotate blades(50) to a position at which none of them are located under a sprinkler.The installer may then program the controller to record that rotationalposition. The controller may then ensure that when fan (10) is stopped(e.g., only in an emergency situation or any time the fan is stopped,etc.), fan (10) will always stop at that programmed rotational position.This may be carried out using electromagnetic braking, mechanicalbraking, or any other suitable techniques. Still other ways in which afan (10) may be brought to a stop in a manner such that a blade (50) isnot undesirably positioned at least partially under a sprinkler headwill be apparent to those of ordinary skill in the art in view of theteachings herein.

Remote Control

Fan system (10) of the present example includes a remote control (500),a merely illustrative example of which is illustrated in FIG. 11. Inparticular, remote control (500) of the present example is a wallmounted unit that is operable to communicate with motor control module(90) wirelessly. For instance, remote control (500) may be configured tocommunicate via RF, such as using Bluetooth, ZigBee, or any othersuitable protocol; or using ultrawideband, infrared, or any othersuitable modality. Alternatively, remote control (500) may communicatewith motor control module (90) via one or more wires or otherwise.

By way of example only, remote control (500) may include a displayscreen (502) and a set of buttons (504, 506, 508, 510, 512). Displayscreen (502) may include an LCD display or any other suitable type ofdisplay. By way of example only, remote control (500) may be similar to(e.g., have any desired features in common with) the remote controldescribed in U.S. Patent Application Pub. No. 2005/0253731, entitled“Movable Barrier Operator System Display Method and Apparatus,”published Nov. 17, 2005, the disclosure of which is incorporated byreference herein. Buttons (504, 506, 508, 510, 512) may be providedunder a membrane, and may comprise thin film switches, capacitiveswitches, or be provided in any other suitable form. In other versions,display screen (502) and buttons (504, 506, 508, 510, 512) are combinedin the form of a touch-screen. In the present example, buttons include a“left arrow” button (504), a “right arrow” button (506), a “next menu”button (508), a “on/off” button (510), and a “light” button (512). Ofcourse, any of these buttons (504, 506, 508, 510, 512) may be varied oromitted, and any other suitable buttons may be used.

Buttons (504, 506, 508, 510, 512) on the remote control (500) may beoperable to turn the fan (10) on or off, control the direction of fanblade (50) rotation (e.g., clockwise or counterclockwise), adjust therotation speed of the fan (10), and to activate lights (100) and/orother auxiliary components (e.g., thermal sensors, humidity sensors,anemometers, external lights, etc.). By way of example only, “on/off”button (510) may be used to turn the fan (10) on or off. A “light”button (512) may be used to turn lights (100) on or off. Arrow buttons(504, 506) may be used to adjust the rotation speed of fan (10). Inparticular, “right arrow” button (506) may be used to increase therotation speed of fan (10) when fan (10) is rotating in a firstdirection; and be used to decrease the rotation speed of fan (10) whenfan (10) is rotating in a second direction. Conversely, “left arrow”button (504) may be used to decrease the rotation speed of fan (10) whenfan (10) is rotating in the first direction; and be used to increase therotation speed of fan (10) when fan (10) is rotating in the seconddirection. In some versions, however, “right arrow” button (506) is usedto increase the rotation speed of fan (10) regardless of the directionof rotation; while “left arrow” button (504) is used to decrease therotation speed of fan (10) regardless of the direction of rotation.

A “reset” button (not shown) may also be included on remote control(500), such as to reset and start fan (10) when a fault condition hasbeen addressed. To the extent that a “reset” button is included, it maybe located such that it is somewhat hidden and/or relatively difficultto activate, such as to prevent inadvertent activation of the “reset”button during normal operation of fan (10). Alternatively, thefunctional equivalent of a “reset” button may be provided by activationof one or more other buttons (504, 506, 508, 510, 512) in a certaincombination and/or pattern, and/or for a certain duration of time.

Various exemplary information that may be indicated by display screen(502), and associated functions that may be effected by buttons (504,506, 508, 510, 512), are shown in FIG. 11. For instance, an icon (520)representing a fan (or any other indication) may be shown on displayscreen (502) to indicate that blades (50) are rotating (e.g., motor (20)is on and rotating blades (50)). Icon (520) may be illuminated whenblades (50) are rotating, and may be dark when blades (50) are notrotating (e.g., motor (20) is off). As another example, icon (520) maybe green when blades (50) are rotating, and may be red when blades (50)are not rotating. As yet another example, icon (520) may rotate whenblades (50) are rotating, and may remain stationary when blades (50) arenot rotating. Alternatively, icon (520) may be used to indicate whetherblades (50) are rotating in any other suitable fashion. Of course, aswith other features described herein, icon (520) may be varied oromitted if desired.

An icon (522) representing a light bulb (or any other indication) may beshown on display screen (502) to indicate whether lights (100) are on.Icon (522) may be illuminated when lights (100) are on, and may be darkwhen lights (100) are off. As another example, icon (522) may be greenwhen lights (100) are on, and may be red when lights (100) are off.Alternatively, icon (522) may be used to indicate whether lights (100)are on or off in any other suitable fashion. Of course, as with otherfeatures described herein, icon (522) may be varied or omitted ifdesired.

An icon (526) representing a right arrow (526) may indicate that fan(10) is rotating in a direction to provide downward airflow. An icon(524) representing a left arrow (524) may indicate that fan is rotatingin a direction to provide upward airflow. Of course, as with otherfeatures described herein, icons (524, 526) may be varied or omitted ifdesired.

A percentage indicator (530) may indicate the rotation speed of fan (10)as a percentage of its maximum rotation speed. Of course, a variety ofother indicators may be used to indicate the rotation speed of fan (10),including but not limited to a representation of a bar, dial, etc.

Display screen (502) of remote control (500) of the present example mayalso be configured to display status and/or error information to theuser. For instance, display field (528) of display screen (502) mayindicate whether remote control (500) is in communication with controlmodule (90) wirelessly, via wire, or not in communication with controlmodule (90). Such an indication may be provided briefly upon startup offan system (10) (e.g., for a few seconds after a user first activates“on” button (510)). To the extent that remote control (500) controlsmore than one fan (10), display field (528) may show how many fans (10)remote control (500) is commanding, and may even provide identificationof which particular fans (10) remote control (500) is commanding. Forinstance, specific fans (10) may be assigned specific fan numbers, anddisplay field (528) may cycle through or scroll, etc., the fan numbersassociated with the fans (10) that remote control (500) is commanding.As another merely illustrative example, and as will be described ingreater detail below, the user may activate “next” button (508) toarrive at a menu permitting the user to select one or more fans (10)from various available fans (10), such as by using arrow buttons (504,506) when the user as at the fan selection menu. Display field (528) maypresent information using bitmaps or other types of image files, usingalphanumeric representations, and/or using any other type(s) ofrepresentations, including combinations thereof.

In the present example, the “next menu” button (508) may be used tocycle through various menus on remote control (500). The display field(528) of display (502) may provide some indication as to which menu iscurrently being accessed, and may also display icons and/or otherinformation associated with the particular menu that is currently beingaccessed. For instance, after the user initially turns on fan system(10), display (502) may show a general control screen. The user may thenactivate “next menu” button (508) to reach an “active fan” menu ondisplay (502). The phrase “active fan” may appear in display field (528)when the “active fan” menu is reached. Alternatively, any other suitableindication may be provided.

The “active fan” menu may permit the user to select which particular fanor fans (10) is or are to be controlled by remote control (500). By wayof example only, fans (10) may be assigned identification numbers orother forms of identification, and the user may cycle through theseidentification numbers by pressing one of the arrow buttons (504, 506)while the “active fan” menu is showing, until the user arrives at anidentifier for a fan (10) that the user would like to control. In someversions, the user may select several fans (10) in this manner withoutleaving the “active fan” menu, then activate “next menu” button (508)until the user reaches the general control screen, and the user may thencontrol all of the selected fans (10) in a synchronous manner. In otherversions, the user selects a first fan (10) through the “active fan”menu, activates “next menu” button (508) until the user reaches thegeneral control screen, then controls the first selected fan (10)through the general control screen, then activates “next menu” button(508) to again reach the “active fan” menu, then selects a second fan(10) through the “active fan” menu, and so on. The first fan (10) maycontinue to run as initially commanded while a control command isentered for the second fan (10). A single remote control (500) may thusbe used to control several fans (10) in a synchronized fashion orindependently of one another.

By actuating “next menu” button (508) again, the user may advance toanother menu. For instance, a “direction” menu may permit a user toselect the direction of fan (10) rotation, such as by using “left arrow”button (504) and “right arrow” button (506) once the “direction” menuhas been reached. The word “direction” may appear in display field (528)when the “direction” menu is reached. Alternatively, any other suitableindication may be provided. “Left arrow” icon (524) and “right arrow”icon (526) may be used to indicate the direction in which fan (10) isrotating or will be rotating. The user may switch the direction ofrotation by activating buttons (504, 506) when the “direction” menu isbeing displayed by display (502). In the present example, fan system(10) provides counterclockwise rotation of blades (50) (as viewed fromthe floor looking up toward fan (10) and the ceiling (210)) by default,though clockwise rotation may be provided by default if desired. Inparticular, hub (40) and blades (50) are configured to provide downwardairflow when hub (40) and blades (50) are rotated counterclockwise. Asnoted above, when a user changes fan (10) rotation direction through“direction” menu, motor (20) may coast to a stop, then reverse itsrotation and increase in speed until it reaches a set rotation speed. Ofcourse, if fan (10) has not yet started to rotate when the user selectsa rotation direction through “direction” menu, fan (10) may rotate inthe selected direction as soon as the user initiates rotation.

By activating “next menu” button (508) yet again, the user may advanceto yet another menu. For instance, an “Aux” menu may permit a user totoggle auxiliary output on or off, such as by using “left arrow” button(504) and “right arrow” button (506) once the “Aux” menu has beenreached. A visual indication in display field (528) may indicate whetherauxiliary output is on or off when the “Aux: menu is being presented.

Yet another additional menu that may be reached by activating “nextmenu” button (508) a sufficient number of times may permit a user toreset an auxiliary fault indication, such as by using “right arrow”button (506) once the auxiliary fault menu has been reached. Still otheralternative menus that may be shown in display screen (502) will beapparent to those of ordinary skill in the art in view of the teachingsherein. In other versions, display screen (502) merely shows a singlemenu or set of options.

Display field (528) may also be operable to indicate whether fan (10) isoperating properly or whether a fault condition is present (e.g., byproviding an error code to indicate the nature of the fault, such asmotor fault, controller fault, temperature fault, imbalance, etc.). Whena fault is detected, display screen (502) may indicate such fault (e.g.,by automatically presenting a fault indication screen), and remotecontrol (500) may be inoperable to control at least part of fan system(10), until such fault is successfully addressed. For instance, when afault is detected, arrow buttons (504, 506) may be inoperable to causefan blades (50) to rotate until the fault is successfully addressed.Similarly, “next” button (508) may be inoperable to cycle away from afault indication screen until the fault is successfully addressed. Inother words, when a fault is detected, display (502) may automaticallydefault to a fault screen until the fault is addressed by the operatoror maintenance personnel. Alternatively, display (502) may show an icon(e.g., an exclamation point in a triangle) on the main control screenwhen a fault is detected, which will indicate to the user that theyshould tap “next” button (508) to cycle the screen on display (502) to afault screen. Of course, remote control (500) could also provide avariety of other types of indications to notify the user of a faultcondition (e.g., flashing light, beeping, etc.).

By way of example only, display field (528) may display any or all ofthe following messages in response to detection of one or more faults,among other types of messages: “imbalance detected—correct fault, thenreset system;” “data link lost—check for power at drive—check wiringconnections;” “motor fault—thermal—service required;” “motorfault—current limit—service required” (e.g., when motor (20) currentexceeds approximately 10 amps); “motor fault—feedback—service required;”“motor fault—stall—service required” (e.g., when current in motor (20)is above minimum and it fails to rotate within approximately 20 secondsof commanding it to run); “motor fault—low AC line—service required;”“motor fault—PFC—service required;” “drive fault—thermal—servicerequired;” “drive fault—power stage—service required;” “drivefault—voltage—service required.” Alternatively, remote control (500) maynotify the user of faults using any suitable text, color(s), graphics,sound(s), etc., including combinations thereof. To the extent that asingle remote control (500) is in communication with a plurality of fans(10), display (502) may also indicate which particular fan (10) a givenfault is associated with. Other faults that a user may be notified of,and various other ways in which a user may be notified of faults, willbe apparent to those of ordinary skill in the art in view of theteachings herein.

In some versions, fan system (10) provides a two-tiered reaction in theevent of a thermal fault in motor (20). As noted above, thermal faultsin motor (20) may be detected using a thermistor or any other suitablecomponent(s). When the temperature of motor (20) exceeds a firstthreshold, the rotation speed of motor (20) may be reduced and thetemperature monitored. If the temperature of motor (20) falls back belowthe first threshold, or falls below some other threshold, the speed ofmotor (20) may be increased back to its previous speed. However, if thetemperature of motor (20) continues to rise, passing a second (higher)threshold, even with the speed of motor (20) being reduced, power tomotor (20) may be stopped such that fan system (10) will be at leastpartially disabled until the temperature of motor (20) drops to anacceptable level. Such a two-tiered reaction may also be provided insituations where the temperature of control module (90) exceeds a firstand second threshold. Of course, thermal faults may be addressed in avariety of other ways if desired. For instance, a single type ofresponse may be provided in response to a fault, such as automaticdisablement of fan system (10) in the event that an impact of blade (50)or imbalance in fan system (10) is detected and/or in the event that the400V bus generated by the PFC has deviated above or below an acceptablerange. Furthermore, automatic reactions to certain faults may have atemporal limit. For instance, if AC line voltage drops below athreshold, fan system (10) may be disabled until the AC line voltagerises again to an acceptable level, whereupon fan system (10) mayautomatically resume normal operation. Still other ways in which controlmodule (90) and/or other components of fan system (10) may react upondetection of one or more faults will be apparent to those of ordinaryskill in the art in view of the teachings herein.

In some versions, remote control (500) may also be used to reset orclear at least some faults, such as using arrow buttons (504, 506) whenan appropriate menu is being presented by display (502). Remote control(500) may communicate with one or more sensors, motor control module(90), and/or any other suitable component(s) to determine whether thefault at issue has been appropriately addressed. If the fault at issuehas not been appropriately addressed yet, display screen (502) may soindicate (e.g., by either not responding to a fault clear attempt or byexplicitly indicating that the fault has not been appropriatelyaddressed, etc.). Furthermore, some faults (e.g., fan imbalance, etc.)may require the operator to access a reset button on or near motorcontrol module (90) before fan (10) may become operational once again,to ensure proper inspection of fan system (10); while other faults maybe reset at remote control (500). Display screen (502) may show whetherfaults have been successfully addressed and cleared, using any suitableindication(s) such as text, color, graphics, sound, etc., includingcombinations thereof.

In addition to or in lieu of the information described above as beingshown on display screen (502), display field (528) of display screen(502) may show a CFM meter (e.g., showing the cubic feet per minute ofair being moved by fan (10)); a velocity meter (e.g., indicating thevelocity of air being moved by fan (10)); day-date-time, temperature(e.g., room temperature, upper and lower air temperature, outsidetemperature, etc.); humidity; power consumption per hour or an energyticker, etc.; system health status; a screen saver logo (e.g., evenpermitting the user to select a screen saver from among severaloptions); and/or any other information or features that are desired toincorporate into display screen (502). Alternatively, a remote control(500) may lack a display screen (502) altogether.

In operation, when a user activates “on/off” button (510), fan system(10) may be turned on, and motor (20) may rotate fan blades (50) towhatever speed they were rotating at when fan system (10) was last used.Alternatively, fan system (10) may simply turn on when a user activates“on/off” button (510), such that motor (20) does not rotate fan blades(50) until the user activates “right arrow” button (506). At that time,motor (20) may rotate fan blades (50) to whatever speed they wererotating at when fan system (10) was last used; or may simply startrotating fan blades (50) at some predefined initial rotation speed, etc.(e.g., at approximately 12% of the maximum rotation speed). To theextent that a previously used rotation speed is used at the initiationof blade (50) rotation, data indicating the previously used rotationspeed may be stored in a memory residing in remote control (500),residing in motor control module (90), and/or residing elsewhere.

As noted above, “right arrow” button (506) may be used to increase therotation speed of fan (10); while “left arrow” button (504) may be usedto decrease the rotation speed of fan (10). In some versions, holding“right arrow” button (506) down will cause the rotation speed of fan(10) to ramp up substantially continuously; while tapping “right arrow”button (506) may cause rotation speed of fan (10) to step up byapproximately 1 RPM (or any other suitable increment) each time “rightarrow” button (506) is tapped. Similarly, remote control (500) may beconfigured such that holding “left arrow” button (504) down will causethe rotation speed of fan (10) to ramp down substantially continuously;while tapping “left arrow” button (504) may cause rotation speed of fan(10) to step down by approximately 1 RPM (or any other suitableincrement) each time “left arrow” button (504) is tapped.

Remote control (500) may also include a battery or other internal powersource and/or a clock. For instance, a battery may provide power to areal time clock in remote control (500). A battery may also providepower to a volatile memory and/or other components in remote control(500). While remote control (500) may also be powered by a pre-existingpower source at the facility in which fan system (10) is installed, andmay rely solely or at least partially on such a pre-existing powersource, a battery may provide backup power to a clock and/or othercomponents in remote control (500) in the event that the main power tothe facility is lost. To the extent that a battery is incorporated intoremote control (500), display (502) may provide one or more messageswhen the battery is low. For instance, display (502) may show a batteryicon or some other icon when the battery is low. Alternatively, display(502) may provide a low battery indication using one or more of theother icons (520, 522, 524, 526), such as by toggling back and forthbetween illuminating and darkening icons (520, 522).

Remote control (500), including any software within remote control(500), may also have any, all, or none of the following aspects: WindowsCE operating system; multi-dialog GUI; self-reboot; password schema toprevent certain software from being uninstalled, modified, or copied(e.g., only permitting administrator, but not a user, to engage in suchoperations); password schema to prevent system settings from beingdeleted or modified (e.g., only permitting administrator, but not auser, to engage in such operations); ability to control multiple fans(10) individually and/or contemporaneously from a single remote control(500); 24/7 fan operation schedule; record error log; providemaintenance reminders (e.g., lamp life, etc.); FM radio, satelliteradio, internet radio, etc. (e.g., providing weather information fordisplay on a display screen and/or to automatically influence fanoperation); atomic clock; audible start signal prior to operation;ability to perform cooling comfort, cubic feet per minute (CFM),velocity calculations (e.g., for automatically adjusting fan speed);ability to interface with an HVAC system (e.g., a TRACE system, etc.);remote access to download data for study or troubleshooting purposes;ability to control fan (10) wirelessly; ability to update firmwarewirelessly; ability to download data wirelessly (e.g., for study ortroubleshooting purposes, etc.); sensors (e.g., for use in coolingcomfort, temperature, humidity calculations, etc.); USB port; RJ45 port;and/or wireless card/chip. Various ways in which such features may beincorporated into remote control (500) and any other associatedcomponents of fan system (10) will be apparent to those of ordinaryskill in the art in view of the teachings herein. Furthermore, othersuitable features that a remote control (500) may include will beapparent to those of ordinary skill in the art in view of the teachingsherein.

In some variations, each fan (10) has a corresponding remote control(500). In other variations, where a plurality of fans (10) are provided(e.g., within the same room, facility, and/or geographic location,etc.), a single remote control (500) may be used to control a pluralityof fans (10). Such control may be “across the board” (e.g., all fans(10) are simultaneously subject to the same commands entered via asingle remote control (500)). Alternatively, a single remote control(500) may be operable to selectively control individual fans (10) withina plurality. For instance, each fan (10) within a plurality of fans (10)may be identifiable and selectable through a single display screen(502), and a single remote control (500) may be used to control suchfans (10) individually and/or in groups. As an example of fan (10) groupcontrol, fans (10) may be grouped per location (e.g., per fans (10)being in the same room within a facility when the facility has variousrooms with fans (10), per fans (10) being within the same building wherea facility has various buildings with fans (10) at common geographiclocation, per fans (10) being within the same facility when there areseveral facilities at different geographic locations, etc., includingvarious selectable combinations and permutations of such groupings).Fans (10) may also be grouped based on a user's ad hoc assignment offans (10) to a control group. Of course, a remote control (500) may beoperable in a plurality of modes, such as a mode permitting “across theboard” control of a plurality of fans (10), a separate mode forcontrolling single fans (10) individually, a separate mode foridentifying fan (10) groups, a separate mode for controlling fans (10)in groups, etc.

Remote control (500) may also include a port that may be used to coupleremote control (500) with some other device, such as for using anotherdevice to transmit software, data (e.g., diagnostic or operationaldata), or commands to remote control (500) via the port. Suchtransmitted software, data, or commands may be stored by and/or used byremote control (500). In addition or in the alternative, remote control(500) may relay at least a portion of such transmitted software, data,or commands to motor control module (90). As yet another variation,motor control module (90) may include such a port. Where motor controlmodule (90) includes such a port, such a port may also be included inremote control (500) or may be omitted from remote control (500). Instill another variation, a port in remote control (500) may be used totransmit software, data, and/or commands to a desktop or laptopcomputer, among other devices.

In addition or in the alternative, a port in remote control (500) and/orin control module (90) may be used to couple fan (10) with a centralizedHVAC control system that is within the facility in which fan (10) isinstalled (e.g., a pre-existing HVAC control system that was installedbefore fan (10)). In other words, remote control (500) and/or controlmodule (90) (and/or any other component of fan system (10)) mayinterface with a facility's centralized HVAC control system, such thatunidirectional or bi-directional communication may be provided betweenfan system (10) and the HVAC control system. Software, data, or commandsmay thus be communicated one way or both ways between fan system (10)and an HVAC control system. For instance, remote control (500) may beused to operate individual HVAC units within a facility that has severalHVAC units. In particular, remote control (500) may be used to operatesuch HVAC units one-by-one, in selected groups simultaneously, allsimultaneously, and/or in any other suitable fashion. Alternatively,such a port may be omitted from fan system (10) altogether.

In some variations, a fan system (10) is provided with a handheld remotecontrol (500). Such a handheld remote control (500) may be provided inaddition to or in lieu of a wall mounted remote control (500). Ahandheld remote control (500) may include the same features as a wallmounted remote control (500), may lack some features (e.g., a displayscreen), or may have additional features that are not present in a wallmounted remote control (500). Of course, other versions of fan system(10) may lack a handheld remote control (500).

Remote Computer

In addition to or as an alternative to a wall mounted unit and/orhandheld unit, a remote control (500) may comprise a personal computeror other computer or device. To the extent that a computer or otherdevice is communicatively coupled with fan system (10), such a computeror other device may send any suitable commands or data to a motorcontrol module (90) or other component of fan system (10). For instance,a remote computer may be used to re-configure the display features andbutton operability of a wall mounted remote control (500) unit.

In addition, a remote computer may receive data (e.g., diagnostics, suchas the diagnostic data described above) from a fan system (10), such asfor analysis and/or storage. Such data may be sent periodically, uponrequest by the remote computer, when one or more certain conditions aredetected, or under any other circumstances. The data may be used todetermine whether maintenance is needed to fan system (10) (e.g., due togeneral wear and tear on the system, due to a particular fault detected,etc.), or for other purposes.

Similarly, data relating to operation of fan (10) may be collected fordetection of misuse of fan (10). For instance, one or more sensors orother components may be used to detect misuse of fan (10). In additionor in the alternative, diagnostic data that is collected as describedabove may be gleaned for indications of misuse of fan (10). Such misuseof fan (10) may be relevant in the event that a user attempts to obtaina refund or replacement under a warranty. Information indicating misuseof fan (10) may be transmitted to a remote computer. In addition or inthe alternative, such information may be stored locally (e.g., in remotecontrol (500)), and acquired via a port or otherwise when servicing fansystem (10).

It will also be appreciated that a remote computer may be located in thesame room or same facility as fan system (10), or may be locatedelsewhere (e.g., in another country), particularly if fan system (10) isin communication with a network such as the internet. For instance, fansystem (10) may communicate with a cell phone, and/or may communicatevia a cell phone modem or use any other suitable means of communication.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

What is claimed is:
 1. A fan system, wherein the fan system comprises:(a) a hub, wherein the hub is configured to rotate about an axis,wherein the hub has a plurality of outwardly extending blade mountingmembers; (b) a plurality of fan blades mounted to the blade mountingmembers of the hub; (c) a drive system in communication with the hub,wherein the drive system is operable to rotate the hub; and (d) aplurality of fan blade retainers, wherein each of the fan bladeretainers is secured to corresponding first and second blade mountingmembers of the hub, wherein each of the fan blade retainers is furthersecured to corresponding first and second fan blades associated with thecorresponding first and second blade mounting members, and furtherincludes an elongated portion extending radially along at least one ofthe first and second fan blades.
 2. The fan system of claim 1, whereinthe blade retainers are generally L-shaped.
 3. The fan system of claim2, wherein the blade retainers each comprise a first portion includingthe elongated portion and a second portion, wherein the first portionextends radially outwardly relative to the axis, wherein the secondportion extends circumferentially about the axis, wherein the firstportion and the second portion are joined at a third portion.
 4. The fansystem of claim 3, wherein each of the blade retainers comprise a firstopening formed through the first portion, a second opening formedthrough the second portion, and a third opening formed through the thirdportion.
 5. The fan system of claim 4, wherein the first and thirdopenings of a first blade retainer are configured to align with openingsformed in a first fan blade, wherein the second opening of the firstblade retainer is configured to align with an opening formed in a secondfan blade.
 6. The fan system of claim 5, wherein the second fan blade isadjacent to the first fan blade.
 7. The fan system of claim 5, whereinthe second opening of the first fan blade retainer is further configuredto align with the third opening of a second fan blade retainer.
 8. Thefan system of claim 3, wherein the third portion of a first bladeretainer overlaps the second portion of a second blade retainer.
 9. Thefan system of claim 1, wherein each blade retainer is configured to bearthe weight of at least one of the fan blades.
 10. A fan system, whereinthe fan system comprises: (a) a hub, wherein the hub is configured torotate about an axis, wherein the hub has a plurality of outwardlyextending blade mounting members; (b) a plurality of fan blades mountedto the blade mounting members of the hub; (c) a drive system incommunication with the hub, wherein the drive system is operable torotate the hub; and (d) a plurality of fan blade retainers, wherein theblade retainers each comprise a first elongated portion and a secondportion, wherein the first portion extends radially outwardly relativeto the axis, wherein the second portion extends circumferentially aboutthe axis, wherein a first retainer associated with a first fan bladeoverlaps with a second retainer associated with a second fan blade. 11.The fan system of claim 10, wherein each retainer is generally L-shaped.12. The fan system of claim 10, wherein the first portion is generallystraight and the second portion is arcuate.
 13. The fan system of claim10, further including a corner at the junction between the first portionand the second portion.
 14. A fan system having a hub configured torotate about an axis and including a plurality of outwardly extendingblade mounting members, comprising: at least one fan blade adapted forbeing mounted to one of the plurality of blade mounting members of thehub; at least one generally L-shaped fan blade retainer for retainingthe fan blade in place on the fan blade mounting member; and at leastone fastener for securing the L-shaped fan blade retainer to the atleast one fan blade.
 15. The fan system of claim 14, wherein the bladeretainer comprises comprise a first portion and a second portion,wherein the first portion extends radially outwardly relative to theaxis, wherein the second portion extends circumferentially about theaxis.
 16. The fan system of claim 15, wherein the first portion isgenerally straight and the second portion is arcuate.
 17. The fan systemof claim 15, further including a corner at the junction between thefirst portion and the second portion.
 18. The fan system of claim 14,wherein the at least one fastener is for securing the L-shaped fan bladeretainer to a next-adjacent fan blade retainer.